#mainbox {
    width: 1007px;
    margin: 0 auto;
    padding: 0;
    border-radius:20px;
}

#header {
    /*background-image: url(../img/header.png);*/
    background-color: dodgerblue;
    width: 1007px;
    height: 52px;
    text-align: center;
    font-family: 幼圆, serif;
    font-size: xx-large;
    font-weight: bold;
    border-radius:20px 20px 0 0;
}

#nav {
    overflow: hidden;
    background-color: lightgray;
    height: 40px;
    text-align: center;
}

#nav li {
    display: inline-block;
    width: 100px;
    height: 20px;
    margin-right: 2px;
    text-align: center;
}

#leftarticle {
    float: left;
    width: 300px;
    height: 600px;
    padding-top: 30px;
    border-right: 2px solid lightgray;
    border-left: 2px solid lightgray;
    text-align: center;
}

#menu td {
    height: 30px;
}

#mainarticle {
    float: left;
    width: 702px;
    height: 600px;
    /*padding-top: 30px;*/
    border-right: 1px solid lightgray;
    border-bottom: 1px solid lightgray;
}

#footer {
    text-align: center;
    background-color: #666666;
    width: 100%;
    height: 50px;
    clear: both;
    font-family: 幼圆, serif;
    border-radius:0 0 20px 20px;
}

a {
    text-decoration: none;
}

span {
    color: brown;
    font-weight: bold;
    font-family: 幼圆, serif;
}

#leftarticle ul {
    color: brown;
    font-weight: bold;
    font-family: 幼圆, serif;
    text-align: left;
}

table{
    margin: 0 auto;
    padding: 0;
    border-collapse: separate;
    border-spacing: 50px 10px;  /* 水平间距 垂直间距 */
    font-size: small;
    font-family: 幼圆, serif;
    color: brown;
    font-weight: bold;
}